[OSPF] Backbone Area

Tom Sanders <toms.sanders@gmail.com> Sat, 16 April 2016 00:43 UTC

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Date: Sat, 16 Apr 2016 06:13:12 +0530
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From: Tom Sanders <toms.sanders@gmail.com>
To: OSPF List <ospf@ietf.org>
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Subject: [OSPF] Backbone Area
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Hi,

OSPF requires all areas to be connected via the backbone. I wanted to
understand why we have this requirement since IS-IS doesnt mandate such a
thing.

I understand that all the border routers summarize and inject the summary
routes inside the backbone. The backbone then does "distance vector
routing" and injects those summaries to other areas.

How does having a backbone eliminate loops is something that i dont
understand. Can somebody explain that to me?

-- 
Toms.